1/*
2 * VIA PadLock support functions
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 */
19/*
20 * This implementation is based on the VIA PadLock Programming Guide:
21 *
22 * http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
23 * programming_guide.pdf
24 */
25
26#include "common.h"
27
28#if defined(MBEDTLS_PADLOCK_C)
29
30#include "mbedtls/padlock.h"
31
32#include <string.h>
33
34/* *INDENT-OFF* */
35#ifndef asm
36#define asm __asm
37#endif
38/* *INDENT-ON* */
39
40#if defined(MBEDTLS_HAVE_X86)
41
42/*
43 * PadLock detection routine
44 */
45int mbedtls_padlock_has_support(int feature)
46{
47 static int flags = -1;
48 int ebx = 0, edx = 0;
49
50 if (flags == -1) {
51 asm ("movl %%ebx, %0 \n\t"
52 "movl $0xC0000000, %%eax \n\t"
53 "cpuid \n\t"
54 "cmpl $0xC0000001, %%eax \n\t"
55 "movl $0, %%edx \n\t"
56 "jb 1f \n\t"
57 "movl $0xC0000001, %%eax \n\t"
58 "cpuid \n\t"
59 "1: \n\t"
60 "movl %%edx, %1 \n\t"
61 "movl %2, %%ebx \n\t"
62 : "=m" (ebx), "=m" (edx)
63 : "m" (ebx)
64 : "eax", "ecx", "edx");
65
66 flags = edx;
67 }
68
69 return flags & feature;
70}
71
72/*
73 * PadLock AES-ECB block en(de)cryption
74 */
75int mbedtls_padlock_xcryptecb(mbedtls_aes_context *ctx,
76 int mode,
77 const unsigned char input[16],
78 unsigned char output[16])
79{
80 int ebx = 0;
81 uint32_t *rk;
82 uint32_t *blk;
83 uint32_t *ctrl;
84 unsigned char buf[256];
85
86 rk = ctx->rk;
87 blk = MBEDTLS_PADLOCK_ALIGN16(buf);
88 memcpy(blk, input, 16);
89
90 ctrl = blk + 4;
91 *ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode^1) - 10) << 9);
92
93 asm ("pushfl \n\t"
94 "popfl \n\t"
95 "movl %%ebx, %0 \n\t"
96 "movl $1, %%ecx \n\t"
97 "movl %2, %%edx \n\t"
98 "movl %3, %%ebx \n\t"
99 "movl %4, %%esi \n\t"
100 "movl %4, %%edi \n\t"
101 ".byte 0xf3,0x0f,0xa7,0xc8 \n\t"
102 "movl %1, %%ebx \n\t"
103 : "=m" (ebx)
104 : "m" (ebx), "m" (ctrl), "m" (rk), "m" (blk)
105 : "memory", "ecx", "edx", "esi", "edi");
106
107 memcpy(output, blk, 16);
108
109 return 0;
110}
111
112/*
113 * PadLock AES-CBC buffer en(de)cryption
114 */
115int mbedtls_padlock_xcryptcbc(mbedtls_aes_context *ctx,
116 int mode,
117 size_t length,
118 unsigned char iv[16],
119 const unsigned char *input,
120 unsigned char *output)
121{
122 int ebx = 0;
123 size_t count;
124 uint32_t *rk;
125 uint32_t *iw;
126 uint32_t *ctrl;
127 unsigned char buf[256];
128
129 if (((long) input & 15) != 0 ||
130 ((long) output & 15) != 0) {
131 return MBEDTLS_ERR_PADLOCK_DATA_MISALIGNED;
132 }
133
134 rk = ctx->rk;
135 iw = MBEDTLS_PADLOCK_ALIGN16(buf);
136 memcpy(iw, iv, 16);
137
138 ctrl = iw + 4;
139 *ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode ^ 1) - 10) << 9);
140
141 count = (length + 15) >> 4;
142
143 asm ("pushfl \n\t"
144 "popfl \n\t"
145 "movl %%ebx, %0 \n\t"
146 "movl %2, %%ecx \n\t"
147 "movl %3, %%edx \n\t"
148 "movl %4, %%ebx \n\t"
149 "movl %5, %%esi \n\t"
150 "movl %6, %%edi \n\t"
151 "movl %7, %%eax \n\t"
152 ".byte 0xf3,0x0f,0xa7,0xd0 \n\t"
153 "movl %1, %%ebx \n\t"
154 : "=m" (ebx)
155 : "m" (ebx), "m" (count), "m" (ctrl),
156 "m" (rk), "m" (input), "m" (output), "m" (iw)
157 : "memory", "eax", "ecx", "edx", "esi", "edi");
158
159 memcpy(iv, iw, 16);
160
161 return 0;
162}
163
164#endif /* MBEDTLS_HAVE_X86 */
165
166#endif /* MBEDTLS_PADLOCK_C */
167